1. Technical Field
The present invention relates to an interactive projector and a system thereof each capable of receiving an instruction of the user to a projected screen with a pointing element.
2. Related Art
JP-A-2012-150636 (Document 1) discloses a projection display device (projector) capable of projecting a projected screen on a screen, and at the same time taking an image, which includes an object such as a finger, with a camera to detect the position of the object using the taken image. The object such as a finger is used as a pointing element for making an instruction to the projection image. In other words, when the tip of the object has contact with the screen, the projector recognizes that a predetermined instruction such as drawing is input to the projected screen, and then redraws the projected screen in accordance with the instruction. Therefore, it is possible for the user to input a variety of instructions using the projected screen as a user interface. The projector of the type capable of using the projected screen on the screen as an inputting user interface as described above is referred to as an “interactive projector.” Further, the object used for making an instruction to the projected screen is referred to as a “pointing element.”
In the typical interactive projector, whether or not an instruction is made using the pointing element is determined in accordance with whether or not the tip of the pointing element has contact with the screen. Therefore, it is important to detect the distance between the tip of the pointing element and the screen. In document 1, although there is described the fact that the template-matching process is performed using the object as a template to thereby detect the object, the detailed study has not been performed on the detection method of the tip position of the pointing element, and therefore, there has been demanded accurate detection of the tip position of the pointing element.